Kosinski made Legacy
I don't think Leto was part of the problem, at least not its biggest problem. The not so earth shattering story combined with low advertising doesn't help the fact that it has been 43 years since the original that this one ties back to.
I started watching the Ed Gein story on Netflix. Pretty interesting. He is so messed up, he is the source of MANY horror books and films. Notably: Psycho, Texas Chainsaw Massacre, and Silence of the Lambs.